Revert "Use interceptors for is-checks (version 2)."

pkg/compiler/lib/src/cps_ir/cps_ir_tracer.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.ir_tracer;
 
 import 'dart:async' show EventSink;
 import 'cps_ir_nodes.dart' as cps_ir;
 import '../tracer.dart';
 
@@ skipping 328 matching lines @@
   }
 
   visitCreateInvocationMirror(cps_ir.CreateInvocationMirror node) {
     String args = node.arguments.map(formatReference).join(', ');
     return "CreateInvocationMirror(${node.selector.name}, $args)";
   }
 
   visitTypeTest(cps_ir.TypeTest node) {
     String value = formatReference(node.value);
     String args = node.typeArguments.map(formatReference).join(', ');
-    String interceptor = node.interceptor == null
-        ? ''
-        : ' ${formatReference(node.interceptor)}';
-    return "TypeTest ($value ${node.dartType} ($args)$interceptor)";
-  }
-
-  visitTypeTestViaFlag(cps_ir.TypeTestViaFlag node) {
-    String interceptor = formatReference(node.interceptor);
-    return "TypeTestViaFlag ($interceptor ${node.dartType})";
+    return "TypeTest ($value ${node.dartType} ($args))";
   }
 
   visitApplyBuiltinOperator(cps_ir.ApplyBuiltinOperator node) {
     String operator = node.operator.toString();
     String args = node.arguments.map(formatReference).join(', ');
     return 'ApplyBuiltinOperator $operator ($args)';
   }
 
   visitApplyBuiltinMethod(cps_ir.ApplyBuiltinMethod node) {
     String method = node.method.toString();
@@ skipping 276 matching lines @@
   }
 
   visitCreateInvocationMirror(cps_ir.CreateInvocationMirror node) {
     unexpectedNode(node);
   }
 
   visitTypeTest(cps_ir.TypeTest node) {
     unexpectedNode(node);
   }
 
-  visitTypeTestViaFlag(cps_ir.TypeTestViaFlag node) {
-    unexpectedNode(node);
-  }
-
   visitApplyBuiltinOperator(cps_ir.ApplyBuiltinOperator node) {
     unexpectedNode(node);
   }
 
   visitApplyBuiltinMethod(cps_ir.ApplyBuiltinMethod node) {
     unexpectedNode(node);
   }
 
   visitGetLength(cps_ir.GetLength node) {
     unexpectedNode(node);
@@ skipping 32 matching lines @@
   @override
   visitYield(cps_ir.Yield node) {
     addEdgeToContinuation(node.continuation);
   }
 
   @override
   visitRefinement(cps_ir.Refinement node) {
     unexpectedNode(node);
   }
 }